1. Field of the Invention
This invention relates to an appartus and method for closing a severed body vessel such as a blood vessel, and more particularly to a method and apparatus for closing a body vessel using a pair of interfitting clip members.
2. Description of the Prior Art
The conventional method for ligating a blood vessel is that a cut end of the blood vessel is manually sutured, i.e., stitched using a thread-like material. In a surgical procedure, to avoid excessive bleeding, the cut ends of the blood vessels or tissure must be ligated quickly and certainly. If the surgeon is not skilled, the operating conditions are difficult or the vessel is not easily accessible, he may not be able to quickly and positively ligate the cut end of the blood vessel using suture material, i.e., tie a knot in the joined ends of the suture. In the conventional method, using suture, two operations are usually required, one to apply a hemostat to clamp the cut end of the vessel and the other to ligate the blood vessel to stop bleeding. For example, when the cut end of the blood vessel is beyond the reach of the surgeon's hand, it may be time-consuming, or even impossible, to suture the cut end of the blood vessel. Consequently, conventional suturing is very troublesome and difficult.
An alternative to ligation, using suture material, is to place a metal "U" shaped clip, sometimes called a "ligating clip", around the blood vessel and then to bring the arms of the clip together using an instrument having a closed action like a pair of pliers. The application of the clip to a blood vessel consits of deforming the "U" shaped clip by pressure around the vessel until the two arms of the clip are in close proximity and causes the complete closure of the blood vessel. In most cases the clips are made of deformable and biocompatible metals such as stainless steel, tantalum and titanium. One such method is shown in U.S. Pat. No. 2,301,622 entitled "Hemostat" and another is shown in U.S. Pat. No. 3,270,745 entitled "Hemostatic Clip Constructions". Many surgeons, however, are still avoiding the use of metal mechanical clip ligating devices, as they present a number of important shortcomings. Such clips generally lack an absolutely secure attachment of the ligating clip to the applicator prior to ligation, for example, when being tranferred between assisting personnel and the surgeon. They may fall off before being used, or may even fall into the patient's body cavity, i.e., into the surgical opening, since the clips are held in the applying instrument by pressure from the jaws, which may be easily disrupted. Applying the clip to the body vessel is difficult because of the fixed and usually small aperture of the applicator. In addition, the applicator is generally a cumbersome device which may be difficult to master.
The use of two-piece plastic clamps or clips of various constuction has been suggested by the patent literature for use in surgery.
In U.S. Pat. No. 3,924,629 entitled "Method For Closing A Cut End Of A Blood Vessel", a two-piece plastic clamp is closed by end flaps which are pushed over the ends of a mating clamp plate. The clamp plates are held in strips in a tool.
A two-piece clamp is shown in U.S. Pat. No. 3,744,495 entitled "Method of Securing Prolapsed Vagina in Cattle". The legs of the clamp members are held in slots in each half of the tool case. The clamp is removed from the tool, after closure, by sliding it out from the slot.
In British Pat. No. 972,371, at FIGS. 1 and 2, a two-piece clamp is used as an artery clamp. The clamp is made of protein-base plastic material absorbable by the living tissue. The two clamp members are locked by deformable arrow-shaped heads and cooperating apertures.
In U.S. Pat. No. 3,916,908 entitled "Disposable Bowel Clamp and Detachable Applicator", a plastic two-piece clamp has two rod members each having a male and female hooking means at their ends. The rod members are frictionally held in their respective jaws until they are clamped together.